/**
 * Copyright (c) 2005-2011 springside.org.cn
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * 
 * $Id: ObjectMapper.java 1627 2011-05-23 16:23:18Z calvinxiu $
 */
package com.se7en.core.mapper;

import java.util.Collection;
import java.util.Date;
import java.util.List;

import org.apache.commons.beanutils.ConvertUtils;
import org.apache.commons.beanutils.converters.DateConverter;
import org.apache.velocity.util.StringUtils;
import org.dozer.DozerBeanMapper;

import com.google.common.collect.Lists;
import com.se7en.core.utils.ReflectionUtils;

/**
 * 对象转换工具类. 1.封装Dozer, 深度转换对象到对象 2.封装Apache Commons BeanUtils, 将字符串转换为对象.
 * 
 * @author calvin
 */
@SuppressWarnings("unchecked")
public abstract class ObjectMapper {

    /**
     * 持有Dozer单例, 避免重复创建DozerMapper消耗资源.
     */
    private static DozerBeanMapper dozer = new DozerBeanMapper();

    /**
     * 基于Dozer转换对象的类型.
     */
    public static <T> T map(Object source, Class<T> destinationClass) {
        return dozer.map(source, destinationClass);
    }

    /**
     * 基于Dozer转换Collection中对象的类型.
     */
    public static <T> List<T> mapList(Collection sourceList, Class<T> destinationClass) {
        List<T> destinationList = Lists.newArrayList();
        for (Object sourceObject : sourceList) {
            T destinationObject = dozer.map(sourceObject, destinationClass);
            destinationList.add(destinationObject);
        }
        return destinationList;
    }

    static {
        // 初始化日期格式为yyyy-MM-dd 或 yyyy-MM-dd HH:mm:ss
        registerDateConverter("yyyy-MM-dd,yyyy-MM-dd HH:mm:ss");
    }

    /**
     * 定义Apache BeanUtils日期Converter的格式,可注册多个格式,以','分隔
     */
    public static void registerDateConverter(String patterns) {
        DateConverter dc = new DateConverter();
        dc.setUseLocaleFormat(true);
        dc.setPatterns(StringUtils.split(patterns, ","));
        ConvertUtils.register(dc, Date.class);
    }

    /**
     * 基于Apache BeanUtils转换字符串到相应类型.
     * 
     * @param value
     *            待转换的字符串.
     * @param toType
     *            转换目标类型.
     */
    public static Object convertToObject(String value, Class<?> toType) {
        try {
            return ConvertUtils.convert(value, toType);
        } catch (Exception e) {
            throw ReflectionUtils.convertReflectionExceptionToUnchecked(e);
        }
    }
}